November 27th, 2006

Debugging nVidia problems is illegal (and sx1 progress)

Did you know, that nVidia problems are illegal to debug? Section 2.1.3:
No Reverse Engineering. Customer may not reverse engineer, decompile, or
disassemble the SOFTWARE, nor attempt in any other manner to obtain the
source code.

I belive we should disable oops printing with nVidia binary modules loaded, so that
users do not accidentaly reverse engineer it ;-).
I talked with Vovan today, and apparently sx1 port is in better shape
than I thought. sx1 is misdesigned and for most things (battery
charging and sound, for example) it is neccessary to communicate with
eGold GSM coprocessor. Unfortunately to do that, multiplexing is
needed, and that is only implemented in userspace.

That means that sx1 is *very* depended on userspace helpers. In
future, it should be possible to push multiplexing into kernel (Harald
may be working on that one?) and fix that uglyness in matter
transparent for userspace.

...ouch, and that thinkfinger thingie... It does not work on many machines. It should be relatively easy to do that, just do dump of working communication (binary-only driver is available even for linux) using usbmon, dump again using thinkfinger, compare and figure out what the critical difference is. I can't do that as I do not have hardware.